The Talmud — and everybody else — ponders the puzzling discrepancy between the two formulations in the Chumash with respect to the Sabbath. One iteration of the Ten Commandments (or “Articles”) in the Chumash uses the word shamor (“keep, guard”), while another uses zachor (“remember”) to describe the broad Sabbath requirement. These two locutions have been midrashically interpreted in different ways, in the broad range of halachic details that the Torah places under rubric of Shabbat.